docs: def is_multi_timeseries_incomplete(nc, variable):
      '''
      Returns true if the variable is an incomplete multidimensional array
      representation of time series. For more information on what this means see
      CF 1.6 §H.2.2
  
      http://cfconventions.org/cf-conventions/v1.6.0/cf-conventions.html#_incomplete_multidimensional_array_representation_of_time_series
  
      :param netCDF4.Dataset nc: An open netCDF dataset
      :param str variable: name of the variable to check
      '''
  
      # x(i), y(i), z(i), t(i, o)
      # X(i, o)
      dims = nc.variables[variable].dimensions
      cmatrix = coordinate_dimension_matrix(nc)
  
      for req in ('x', 'y', 't'):
          if req not in cmatrix:
              return False
      if len(cmatrix['x']) != 1:
          return False
      if cmatrix['x'] != cmatrix['y']:
          return False
      if len(cmatrix['t']) != 2:
          return False
      if cmatrix['x'][0] != cmatrix['t'][0]:
          return False
  
      i = cmatrix['x'][0]
      o = cmatrix['t'][1]
  
      if dims == (i, o):
          return True
      return False